Tapered manifold stock distribution system for a papermaking machine with movable wall therein

ABSTRACT

THE DISCLOSED STOCK DISTRIBUTION SYSTEM PROVIDES AUTOMATIC AND CONTINUOUS ADJUSTMENT TO VARIATIONS IN STOCK FLOW VELOCITY IN A PAPERMAKING APPARATUS. A TAPERED MANIFOLD COMMUNICATES ACROSS A FLOW CHANNEL TO DISTRIBUTE PAPER STOCK UNIFORMLY ONTO THE FOURDINIER WIRE. THE TAPERED MANIFOLD CONTAINS A SEMIRIGID DIAPHRAGM WHICH FORMS A WALL OF THE INTERIOR MANIFOLD CHAMBER. SENSORS ARE PROVIDED ACROSS THE WIDTH OF THE FLOW CHANNEL TO MONITOR STOCK FLOW AND DETECT FLOW VELOCITY IRREGULARITIES. EACH SENSOR CONTROLS THE SHAPE OF THE TAPERED MANIFOLD DIAPHRAGM AT A POSITION CORRESPONDING TO THAT OF THE SENSOR. THE EFFECTIVE TAPE OF THE MANIFOLD IS THUS CHANGED AT THE CORRESPONDING POSITION PERMITTING THE VELOCITY OF STOCK ISSUING FROM THAT POSITION IN THE MANIFOLD TO BE ADJUSTED TO A REFERENCE LEVEL. THE INVENTION FURTHER PROVIDES MEANS FOR DISCHARGING FLUID FROM THE LEADING EDGES OF DEFLECTORS AND SPACERS IN THE FLOW CHANNEL TO PREVENT FIBER HANG-UP. ALSO, MEANS ARE PROVIDED FOR APPLYING EXTERIOR PRESSURE TO THE FLOW CHANNEL TO PREVENT DISTORTION OR RUPTURE DUE TO HIGH INTERNAL PRESSURES.

March 30, 1971 OMS 3,573,160

K. L TAPERED MANIFOLD STOCK DISTRIBUTION SYSTEM FOR A PAPERMAKINGMACHINE WITH MOVABLE WALL THEREIN Filed Jan. 29, 1969 4 Sheets-Sheet 1INVENTOR. KAS/M/R LOPAS BY BLA/R, CESAR/ AND 57. ONGE A TTORNEYS March30, 1971 K. LOPAS PAPERMAKING MACHINE W Filed Jan. 29, 1969 1TH MOVABLEWALL THEREIN 4 Sheets-Sheet 2 BLA/R, CESAR/ AND 87. ONGE ATTORNEYS March30, 1971 OPAS 3,573,160

K. L TAPERED MANIFOLD STOCK DISTRIBUTION SYSTEM FOR A PAPERMAKINGMACHINE WITH MOVABLE WALL THEREIN Filed Jan. 29, 1969 -4 Sheets-Sheet 5ATTORNEYS Marsh 30, 1971 K, LQPAS 3573,16 TAPERED MANIFOLD STOCKDISTRIBUTION SYSTEM FOR A v PAPERMAKING MACHINE WITH MOVABLE WALLTHEREIN Filed Jan. 29,' 1969 4 Sheets-Sheet 4 INVENTOR. KA SIM/R LOPA 5BY BLAIR, CESAR! AND SZONGE ATTORNEYS United States Patent 3,573,160TAPERED MANIFOLD STOCK DISTRIBUTION SYSTEM FOR A PAPERMAKING MACHINEWITH MOVABLE WALL THEREIN Kasimir Lopas, 118 Skyview Drive, Stamford,Conn. 06902 Filed Jan. 29, 1969, Ser. No. 794,863 Int. Cl. D21f 1/06 US.Cl. 162259 9 Claims ABSTRACT OF THE DISCLOSURE The disclosed stockdistribution system provides automatic and continuous adjustment tovariations in stock flow velocity in a papermaking apparatus. A taperedmanifold communicates across a flow channel to distribute paper stockuniformly onto the Fourdrinier wire. The tapered manifold contains asemirigid diaphragm which forms a wall of the interior manifold chamber.Sensors are provided across the width of the flow channel to monitorstock flow and detect flow velocity irregularities. Each sensor controlsthe shape of the tapered manifold diaphragm at a position correspondingto that of the sensor. The elfective tape of the manifold is thuschanged at the corresponding position permitting the velocity of stockissuing from that position in the manifold to be adjusted to a referencelevel. The invention further provides means for discharging fluid fromthe leading edges of deflectors and spacers in the flow channel toprevent fiber hang-up. Also, means are provided for applying exteriorpressure to the flow channel to prevent distortion or rupture due tohigh internal pressures.

BACKGROUND OF THE INVENTION In the manufacture of paper sheet, dilute,fibrous paper stock is discharged in a sheet-like stream from anelongated nozzle or slice onto a moving screen (Fourdrinier wire) fordrying. It is important that the flow of stock onto the wire be keptuniform in a spatial and temporal sense so that a smooth, even layer ofstock is continuously laid on the wire. This permits the production ofhigh quality paper, free from imperfections and of uniform consistencythroughout.

In the past, however, it has been extremely diflicult to achieve auniform flow of paper stock from the slice. The fluid stock is generallydelivered to a headbox containing the slice through a delivery systemcomprising round pipe. The fluid must then make the transition from flowin round pipe to flow through the generally rectangular crosssection ofthe headbox. This transition has resulted in flow irregularities whichproduce velocity differentials across the stream discharged from theslice, resulting in lack of uniformity in the layer on the wire andeventually in the final paper sheet.

Accordingly, a tapered manifold stock distributor has been devised forthe stock flow transition. In general this is a tubular chamber intowhich the stock is introduced with the direction of flow thereofgenerally perpendicular to the direction of flow in the headbox. Meansare provided along the length of the tapered manifold to graduallydivert portions of the stock flow into the headbox. A small portion ofthe stock is also permitted to flow straight through the manifold to anoutlet to be recirculated.

It will be understood that since stock is being gradually diverted outof the tapered manifold along the length thereof, there is a gradual butcontinuous drop in the volume of stock in the manifold in the directionof flow and accordingly a drop in flow pressure. The manifold is thusconstructed with a tapering cross-sectional area in the direction ofstock flow to compensate for the volume change. This change incross-sectional area requires careful design so that the flow of thestock diverted to the headbox along the length of the .manifold remainsuniform. If the flow is not maintained uniform, i.e., if the flow of thediverted stock at one end of the manifold differs substantially fromthat at the other end, the flow differentials may persist through theheadbox and out the slice to produce a non-uniform layer of stock on theFourdrinier wire resulting in poor quality paper.

The problem with prior art tapered manifolds is that the degree oftaper, which is fixed, is dependent upon a number of factors includingstock consistency and velocity. These factors however are variable, andsubject to constant change as the papermaking process continues. Theprior art solution has been to design the manifold tape for ananticipated average stock flow. Significant variations in stock flow inthe manifold, however, still produce flow differentials at the slicewhich affects paper quality.

Accordingly, representative objects of the present invention are toproduce a variable, tapered manifold stock distribution system capableof automatically adjusting to variations in stock flow velocity and ofproducing a smooth and uniform flow onto the Fourdrinier wire of apapermaking apparatus.

Other objects of the invention will in part be obvious and will in partappear hereinafter.

The invention accordingly comprises the features of construction,combinations of elements, and arrangement of parts which will beexemplified in the constructions hereinafter set forth, and the scope ofthe invention will be indicated in the claims.

SUMMARY OF THE INVENTION The present invention relates to a variable,tapered manifold stock distribution system for papermaking apparatus andmore particularly to a tapered manifold stock distribution system inwhich the interior cross-section of the manifold is automaticallyvaried, to compensate for variations in the flow of stock in the systemand to provide uniform flow at the slice.

The variation in the cross-section of the tapered manifold of theinvention is accomplished by means of a semirigid elastomer diaphragmsecured within the manifold and comprising a wall of the interiormanifold chamber. Adjustment means are provided to flex the diaphragm atpredetermined positions to effectively change the crosssectional area ofthe manifold at that position. This in effect changes the manifold taperat that position to compensate for varying conditions of stock flow orconsistency.

The means causing flexure of the diaphragm are controlled by sensors inthe distribution system between the tapered manifold and the slice. In apreferred embodiment the sensors are placed in a flow channel which isconnected to the tapered manifold at one end and which has the slice atthe opposite end thereof. The sensors are preferably spaced over thewidth of the flow channel; however, in situations where a headbox or thelike rather than a flow channel is used, the sensors may be placed inthe pipes or spreaders connecting it to the manifold, or in the headboxitself.

The sensors are preferably of the fluid velocity sensitive type andmonitor the stock velocity at predetermined spaced intervals in the flowchannel. If stock velocity exceeds or falls below a predetermined level,the sensors detect the change and actuate means causing flexure atcorresponding positions in the manifold diaphragm. The flexure resultingalters the manifold taper to compensate for either the excess ordeficient stock velocity at the sensor location. Thus a substantiallyuniform stock velocity profile is maintained in the distribution systembetween the tapered manifold and the slice so as to obtain a uniformflow of stock onto the Fourdrinier wire.

The invention also provides for novel deflectors and spacers in the flowchannel. The deflectors act to divert the stock flow from the manifoldto the flow channel while the spacers reinforce the flow chamber andfacilitate the even flow of stock therethrough. Means are provided forpurging the deflectors and spacers with fluid to prevent the hang-up ofstock fibers on the leading edges thereof. The purging may be done withwhite water recirculated from within the distribution system or withpurge water supplied from a separate source.

The invention further provides means for supporting the distributionsystem which includes means for applying fluid pressure to the exteriorof the flow channel. This prevents the deflection or rupture of the flowchannel as a result of the high internal pressure generated during thepapermaking operation.

BRIEF DESCRIPTION OF THE DRAWINGS For a fuller understanding of thenature and objects of the invention, reference should be had to thefollowing detailed description taken in connection with the accompanyingdrawings in which.

FIG. 1 is a side elevation view in section taken along line 11 of FIG. 2showing the distribution system of the invention in position in apapermaking apparatus.

FIG. 2 is a top plan view of the distribution system of FIG. 1 with aportion broken away to show the deflectors and spacers in the interiorof the flow channel.

FIG. 3 is an enlarged sectional view of a portion of the stockdistribution system taken along line 3-3 of FIG. 2, and illustratingdiagrammatically the hydraulic system which controls actuation of thevariable, tapered manifold.

FIG. 4 is a greatly enlarged top plan view of a deflector of theinvention.

FIG. 5 is a greatly enlarged top plan view of a spacer of the invention.

FIG. 6 is a sectional view of a spacer in position in the distributionsystem taken along line 66 of FIG. 5.

FIG. 7 is a greatly enlarged partial sectional view of a portion of thevariable, tapered manifold of the invention.

FIG. 8 is a partial sectional view taken along line 88 of FIG. 2 andlooking down the stock distribution system.

Similar reference characters refer to similar parts throughout theseveral views of the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1 there isshown the stock distribution system of the invention in position in apapermaking apparatus. In general the system comprises a variable,tapered manifold 10 supported on a pedestal 12. Dilute, fibrous paperstock is fed through manifold 10 and into a flow channel 14 whichcomprises an elongated chamber of generally rectangular cross-sectionssupported from below by posts 16 and from above by beams 18. Flowchannel 14 terminates at the end opposite manifold 10 in an elongatednozzle or slice 20 from which stock is discharged onto a movingFourdrinier wire 22 shown supported on a breast roll 24 adjacent slice20.

More particularly, as shown in FIG. 2, tapered manifold 10 comprises agenerally tubular member 26 of tapering cross-section. The taperproceeds from a relatively large inlet opening 28 through which stockenters the distribution system, to a relatively small outlet opening 30through which a portion of the stock flow is recirculated in thepapermaking apparatus.

As shown in FIG. 3, manifold 10 contains an interior manifold chamber 32defined by the sidewalls 34 of tubular member 28 and by a semirigiddiaphragm 36 preferably formed of an elastomeric material. Diaphragm 36is secured in fluid tight relation to the manifold sidewall 34 by rivetsor bolts 38, and is positioned on sidewall 34 to leave a separate smallchamber 40 below. Reinforcement against excessive axial flexure ispreferably provided in diaphragm 36 by a series of reinforcing rods 42(FIG. 7) molded into and running the length of diaphragm 36 in thedirection of stock flow.

To change the effective taper of manifold 10 and thus compensate forstock flow irregularities, means for altering the shape of diaphragm 36comprise a plurality of pistons 44 secured to diaphragm 36 at intervalsalon the length thereof as shown in FIG. 8. The spacing of pistons 44will depend upon a number of factors and may vary from machine tomachine dependent upon design and intended application. For mostapplications however, a spacing of about one foot will be satisfactory.Leaf spring supporters 46 are preferably mounted on each piston 44 belowand in contact with the bottom of diaphragm 36 as shown in FIG. 7 toprovide lateral support. 'Each piston 44 passes through manifold wall 34below chamber 40 (FIG. 7) and is actuated normal to the surface ofdiaphragm 36 in the direction of the arrows shown in FIG. 8. The forceof piston 44 is distributed evenly across diaphragm 36 by the action ofleaf spring support 46. The actuation of each piston 44 may be doneelectrically or mechanically, but preferably it is done hydraulically bymeans of a hydraulic cylinder 48 connected to each piston 44 belowmanifold 10. The hydraulic system for actuating cylinders 48 isdiscussed in more detail below.

Referring now to FIG. 3, the upper portion of manifold 10 is open and isprovided with edge flanges 50 and 52 which are connected by bolts 54 and56 respectively to the flanged ends 58 and 60 of flow channel 14. Flowchannel 14 thus closes the opening in manifold 10 and communicates withinterior manifold chamber 32 to convey paper stock from manifold 10 toslice 20 as shown in FIG. 1.

Flow channel 14 comprises a closed rectangular chamber 62 formed by flattop and bottom plates 64 and 66 spaced apart in parallel planes andwelded or similarly joined by side plates 68 and 70 (FIG. 2). Top plate64 is angled downward (FIG. 1) at the end of flow channel 14 adjacentthe Fourdrinier wire 22 to form with bottom plate 66 an elongated slice20. Preferably, the downwardly angled portion of slice 20 is hinged orotherwise made adjustable so that the spice opening 21 can be varied asdesired.

Referring to FIG. 2, it can be seen that the direction of stock flow inmanifold 10 is at right angles to the axial direction in which the stockflows in channel 14. Accordingly, means are provided to divert the stockflow from manifold 10 to flow channel 14. These means comprise aplurality of deflectors 72 of generally hydrofoil shape (FIG. 4) mountedin flow channel 14 adjacent the area of communications with manifold 10.Each deflector is provided with a plurality of bolt holes 74 and ismounted by bolts 76 (FIG. 3) in flow channel 14 between top plate 64 andbottom plate 66. Deflectors 72, in addition to diverting stock flow,serve both to support top plate 64 and to maintain the proper spacingbetween top plate 64 and bottom plate 66.

As shown in FIG. 4, the leading edge 78 of each deflector 72 is curvedin a manner to intersect the stock flow in manifold 10, and to smoothlydeflect it at an angle through the inter-deflector spaces 79 (FIG. 8)and ito axial flow in flow channel 14. A problem arises, however, withthe use of deflectors since fibers from the paper stock solution have atendency to become caught on or to hangup on the deflector leading edge78. To prevent this, means are provided to discharge fluid from leadingedge 78 against the direction of stock flow. Referring to FIG. 4, arecess 80 is provided adjacent leading edge 78. A channel 82communicates with recess 80 and opens onto the front of leading edge 78.As shown in FIG. 3, when each deflector 72 is mounted in the stockdistribution system an inlet 84 is connected through top plate 64 intorecess 80. Inlet 84 carries fluid (preferably white water recirculatedfrom the papermaking process or purge 'water from a separate source)into recess 00 where it flows out channel 82 against the flow of paperstock to dislodge any accumulated fibers on leading edge 78.

In addition to dflectors 72, spacers 84 (FIGS. 1 and 2) are positionedin groups at ntervals along flow channel 14 between top plate 64 andbottom plate 66. The groups of spacers 84 are positioned between theposts 16 and beams 18 which support flow channel 14. The function ofspacers 84 is to support top plate 64 of flow channel 14 and to maintainthe separation of top and bottom plates 64 and 66. Spacers 84 arepreferably hydrodynamically shaped as shown in FIG. to permit the stockto flow smoothly thereover. Spacers 84 thus minimize flow irregularitiesn flow channel 14.

1 As with deflectors 72, spacers 84 are provided with bolt holes 86 andare mounted by bolts 88 in flow channel 14 as shown in FIG. 6. Eachspacer 84 is also provided Wlth a recess 90 connected by a channel 92 tothe leadmg edge 94 thereof (FIG. 5); they are mounted in flow channel 141n communication with an inlet tube 96 (FIG. 6) so that white water orpurge water can be discharged through channel 92 to prevent hang-up ofpaper stock fibers on din ed e94.

as d iscu ssed above, the shape of diaphragm 36 is altered to change theeffective taper of manifold in order t: compensate for any flowirregularities in flow channel 1 Accordingly, means are provided tosense flow irregularities in flow channel 14, and to effect a change ofshape in diaphragm 36. These means compns'e1 a plurality of velocitysensitive sensors 98 spice at predetermined intervals over the width ofOVfV channel 14 (FIG. 2) and extending into the interior of flow channel14 as shown in FIG. 3. One suitable type 0 sensor is a purged Pitottube. Sensors 98 may be placed in any position in flow channel 14 butare preferably spaced from deflectors 72 so as not to be effected by anyturbulence caused by the diverslon of stock flow from manifold 10.Sensors 98 signal and control the actuation of pistons 44 (FIG. 8) whichare connected to and regulate the shape of diaphragm 36. Sensors 98 mayexert their control through electrical, mechanical, pneumatic or likemeans; preferably, however, they control pistons 44 throughpressurization of a hydraulic system as shown in FIG. 3.

Specifically, each sensor 98, except the reference sensor 98R, ishydraulically connected to the cylinder 48 of the piston 44 at acorresponding position in manifold 10. A hydraulic line 100 connectseach sensor 98 to one side of its pressure differential valve 102. Eachpressure valve 102 comprises a valve cylinder 104 contalning a valvepiston 106 freely mounted for axial movement therein. Valve plston 106carries enlarged end plugs 108 and 110 WhlCh respectively serve to openand close valve inlet 112 and outlet 114 as piston 106 moves axiallywithin valve cylinder 104. Valve inlet 112 is connected to an externalsource of hydraulic pressure while outlet 114 serves as a pressurerelief valve. Valve piston 106 is biased towards the center of valvecylinder 104 by a pair of coil springs 116 and 118 at either end ofpiston 106. The tension on springs 116 and 118 is adjusted throughscrews 120 and 122 which have washers 124 and 126 aflixed to the endpressing against springs 116 and 118. As will be seen from the followingdiscussion, the pressure level at which valve 102 will be actuated maybe regulated by adjustment of screws 120 and 122.

The reference sensor 92R is preferably located at the center of flowchannel 14, although it may be located at any of the sensor positionsshown in FIG. 2. By placing the reference sensor at the center, however,the amount of deflection required in diaphragm 36 is optimallyminimized. Accordingly, the system is adjusted so that the velocity atsensor 98R is at a desired level for the anticipated volumetric rate;thereafter the velocity in any other portion of flow channel 14 may bereferenced thereto. Of course if the flow rate changes the referencevelocity level changes. The reference velocity is established by fixingthe height of piston 44R, the piston corresponding in position toreference sensor 98R as shown in FIG. 8.

Although reference sensor 98R is not connected to piston 44R in manifold10, it is hydraulically connected to each pressure valve 102 of theother sensor 98. Referring back to FIG. 3, a hydraulic line 128 fromreference sensor 98R is connected into each pressure valve 102 at theend opposite the connection from the corresponding velocity sensor 98.Thus, the pressure in the valve chamber surrounding spring 116 dependsupon the velocity at reference sensor 98R and this will be the case ineach pressure valve 102 in the system.

As is further shown in FIG. 3, a hydraulic line 130 connects the bottomof each hydraulic cylinder 48 to the center of the correspondingpressure valve 102 while the other side of cylinder 48 is hydraulicallyconnected with the small chamber 40 below diaphragm 36. It is preferablethat the pressure in chamber 40 be kept equal to or slightly below,e.g., about 0.5 p.s.i.. below the pressure in manifold chamber 32. Forthis purpose a differential pressure regulator 132 having hydrauliclines 134 and 136 respectively connected into manifold chamber 32 andchamber 40 is provided in the system.

Stock fibers tend to accumulate or hang-up on the leading edge 138 ofeach sensor 98, and also about the opening 140 from manifold chamber 32to pressure regulator 132, in a manner similar to that discussed withreference to deflectors 72 and spacers 84. To prevent suchaccumulations, a rotometer 142 (-FIG. 3) is connected into each sensor98 and 98R and discharges a fluid against the flow of stock; the fluidmay be white water recirculated from Within the system or purge waterfrom an outside source. A similar rotometer 144 is connected intohydraulic line 134 of pressure 132 to maintain ,opening 140 clear.

The operation of the distribution system of the invention can best beunderstood with reference to FIG. 3. Assume that the stock flow at theposition in flow channel 14 monitored by the sensor 98 has a highervelocity than the reference stock flow at sensor 98R. Under theseconditions line becomes pressurized by sensor 98 and thus pressurizesthe chamber surrounding spring 118 in pressure valve 102. Since thepressure at the opposite end of pressure valve 102, that is in thechamber surrounding spring 116, is maintained at the reference pressure,valve piston 106 is forced to the left, opening inlet 112. High pressurefluid from the source to which inlet 112 is connected is thus permittedto enter the valve chamber between plugs 108 and and pressurizeshydraulic line this in turn causes piston 44 to rise, deflecting orflexing diaphragm 36 upwardly at that position. Manifold 10 is thusdecreased in cross sectional area in the vicinity of the upwardlyactuated piston 44.

The decrease in manifold cross section in an area results in a decreasedflow of stock through the deflectors 72 in that same area. Thus, adecreased flow of stock occurs all the way down fiow channel 14 in linewith the upwardly deflected portion of diaphragm 36, which means adecreased flow against the sensor 98 under discussion. The decreasedstock flow at sensor 98 causes the pressure to drop in line 100 with aconcomitant drop in pressure in the valve chamber surrounding spring118. The pressure drop permits valve piston 106 to be pushed to theright by the combined action of spring 116 and the reference pressure inthe chamber surrounding spring 116. When the pressure in the chambersurrounding spring 118 drops to the reference pressure in the chambersurrounding spring 116, piston 106 stops and comes to rest at a neutralposition shown in FIG. 3 wherein it closes off both inlet 112 and outlet'114.

It can be seen that a reverse cycle of movement of piston 44 and asimilar but reversed correction will occur if the flow velocity atsensor 98 should be diminished below the reference flow at sensor 98R.

In the manner described above, the distribution system of the inventioncontinuously and automatically adjusts itself to any variation in stockflow velocity across flow channel 14. Thus, flow velocity variationsacross the flow channel are substantially eliminated by constantlyadjusting diaphragm 36 to provide flow velocities corresponding to thevelocity sensed at reference sensor 98R.

Another problem arises in stock distribution systems due to the greatpressures which are built up inside the flow channel during operation.These pressures may amount to to p.s.i. when stock is flowing and thisresults in extremely high pressure forces on the upper and lower plates64 and 66, which may be 100 to 250 inches in width. Such high pressuremay cause the plates 64 and 66 to buckle or may rupture the bolts 76 and88 (FIGS. 3 and 6) which secure plates 64 and 66 about the deflectors 72and spacers 84. Deflection of plates 64 and 66 will change the volume offlow channel 14 and thus introduce irregularities in the stock flow. Tocounteract internal pressure and prevent deflection or rupture of flowchannel 14, a rolling diaphragm 146 is mounted (as shown in FIG. 3) inthe space between each beam 18 and the support bar 148 upon which beam18 rests on top plate 64. The walls of rolling diaphragm 146 define aninternal pressure chamber 150 which may be pressurized with fluidthrough an inlet 152 to counteract the internal pressure within flowchannel 14. An equal and opposite reaction force to the pressure withinrolling diaphragm 146 occurs against bottom plate 66 through interactionwith the support plate 154 atop post 16. While four assemblies of beam18, rolling diaphragm 146 and post 16 are shown in FIGS. 1 and 2, thenumber of assemblies necessary to support a given flow channel 14 willvary and will depend upon the design pressure of the system and theinherent structural strength of the flow channel assembly.

It will thus be seen that the objects set forth above, among those madeapparent from the preceding description, are efliciently attained and,since certain changes may be made in the above constructions withoutdeparting from the scope of the invention, it is intended that allmatter contained in the above description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense.

It is also to be understood that the following claims are intended tocover all of the generic and specific features of the invention hereindescribed, and all statements of the scope of the invention, which, as amatter of language, might be said to fall therebetween.

Having described my invention, what I claim as new and desire to secureby Letters Patent is:

1. A stock distribution system for a papermaking machine comprising incombination:

(A) a tapered manifold (1) containing an interior manifold chamber,

(B) means within said tapered manifold forming a movable wall of saidinterior manifold chamber,

(C) distribution means in communication with said manifold chamber forconveying stock therefrom to a slice,

(D) sensing means for sensing variations in stock flow velocity acrosssaid distribution means, and

(E) adjustment means connected to said sensing means and connected tosaid movable wall means for adjust ing the positioning of said wallmeans in response to signals from said sensing means to compensate forthe stock flow variation and adjust the stock flow to a referencevelocity level.

2. A stock distribution system as defined in claim 1 wherein saiddistribution means comprises a flow channel communicating at one endwith said tapered manifold and incorporating a slice at the opposite endthereof for the discharge of fibrous paper stock onto the F ourdriuierwire of a papermaking apparatus.

3. A stock distribution system as defined in claim 1 wherein said meansforming said movable wall of said interior manifold chamber comprises asemi-rigid diaphragm.

4. A stock distribution system as defined in claim 3 wherein saidsensing means comprises a plurality of fluid velocity sensors spaced atpredetermined intervals over the width of said distribution means.

5. A stock distribution system as defined in claim 4 wherein saidadjustment means for moving said semi-rigid diaphragm comprises aplurality of pistons spaced along the length of said diaphragm andconnected thereto at predetermined intervals, each said pistons beingconnected to and responsive to actuation by one said sensor at acorresponding position in said distribution means to exert pressure onand alter the shape of said diaphragm in a manner to adjust the velocityof stock flow at said position to a reference velocity level.

6. A paper stock distribution system for use in papermaking apparatuscomprising in combination:

(A) a tapered manifold (1) containing an interior manifold chamber,

(B) a flow channel (1) communicating at one end with said taperedmanifold and (2) incorporating a slice at the opposite end thereof forthe discharge of fibrous paper stock onto the Fourdrinier wire of thepapermaking apparatus,

(C) a plurality of fluid velocity sensors 1) spaced at predeterminedintervals over the width of said flow channel,

(D) a diaphragm (1) comprising a wall of said interior manifold chamber,and

(E) a plurality of pistons (l) spaced along the length of said diaphragmand connected thereto at predetermined intervals,

(2) each said piston being actuated by a said sensor at a correspondingposition in said flow channel to exert pressure on and to alter theshape of said diaphragm and thereby change the interior cross section ofsaid tapered manifold whereby the velocity of stock flow within saidflow channel is maintained substantially constant.

7. A stock distribution system as defined in claim 6 including aplurality of deflectors in said flow channel in the area ofcommunication with said tapered manifold, said deflectors being shapedto divert the flow of stock from one direction in said tapered manifoldto another direction in said flow channel and including means thereonfor discharging fluid from the leading edges thereof against thedirection of stock flow to prevent the accumulation of paper stockfibers on said leading edge.

8. A stock distribution system as defined in claim 6 and furtherincluding a plurality of spacers in said flow channel aligned with thedirection of stock flow in said flow chamber and each having meansthereon for dis charging fluid from the leading edge thereof against thedirection of stock flow to prevent the accumulation of paper stockfibers on said leading edge.

9. A stock distribution system as defined in claim 6 including supportmeans for said flow channel having means for applying fluid pressure toat least one wall of said flow channel to counteract the forces ofinternal pressure and prevent substantial deflection of said wall.

References Cited UNITED STATES PATENTS 3,351,522 11/1967 Lopas l62343XS. LEON BASHORE, Primary Examiner R. H. TUSHIN, Assistant Examiner US.Cl. X.R.

